[Antennaware] When is a stub not just a stub

[i4jmy at iol.it (Maurizio Panicara)]

To answer your question, unless common mode currents are flowing on the
outer conductor of the coax, but this should be prevented, nothing will
change if the stub is placed at 90? or not.
Everything that happens in a coax tramission line is (should be) confined
inside it.
The above isn't applicable with open wire lines were a 90? placement of
stubs is needed.
The same concepts is valid for phased antennas (i.e. a quarter wave plus an
half wave in phase) were stubs act as phase shift devices.

73,
Mauri I4JMY